The snow pile at the end of the driveway is finally a puddle. Under it: a white salt crust, sand everywhere, a chip missing where the plow caught an edge, and a sidewalk square that sits lower than you remember.
Spring is when winter's damage shows. It's also the best time to fix small problems before they become expensive ones.
The catch is order. Some jobs can start the first warm day in March. Others have to wait for thawed ground and steady temperatures, and doing them early wastes time and money.
Why Spring Is When Problems Surface
Three things are happening under your concrete between March and May.
- The ground thaws from the top down. That's why Wisconsin puts spring weight limits on roads: the top layer thaws first, and meltwater gets trapped above soil that's still frozen. Those limits average from about early March into early May, and the soil under your slabs goes through the same soft, soggy stretch.
- Snowmelt soaks the weakest soil. The loose backfill along your foundation takes in every downspout, sump discharge, and melting snow pile. Wet, loose soil compresses and washes out, and the slabs on top follow it down.
- Frost heave lets go. Slabs pushed up over winter drop back as the ground thaws, and not always to where they started.
Add a winter of salt, plows, and shovels, and you have the reason for this checklist.
The Checklist, Month by Month
| Month | Do this | Hold off on |
|---|---|---|
| March | Rinse salt residue on above-freezing days. Keep downspout outlets and splash blocks clear of ice. Watch where meltwater pools and photograph it. Take "before" pictures of anything that looks off. | Judging sinking or heave. Caulking, sealing, and lifting all wait for thawed ground and warmer weather. |
| April | Sweep up winter sand. Rake plowed gravel and sod back off the edges. Check downspouts and the sump outlet as spring rain picks up. Do your first walk-around (below). Send photos for any lifting quote. | Sealing. Green Bay's normal April low is about 35°F, below the 40°F minimum on most sealer labels we checked. Final calls on heaved slabs. |
| May | Re-measure anything that looked low in March. Deep clean, then lift sunken slabs. Caulk joints and the house gap once the concrete is dry, frost-free, and 40°F or warmer. Fill washouts along slab edges and slope the soil away. | Sealing over caulk that hasn't cured, or over concrete still damp from washing. |
| June | Seal clean, dry concrete once the caulk has cured and temperatures fit the label. Sweep fertilizer granules off drives and walks. Do a final walk-around and compare against your March photos. | Letting a sunken slab ride another season. Every rain sends more water toward the void under it. |
If sealing doesn't happen by June, don't sweat it. Late summer into early fall is the other good window.
The 10-Minute Walk-Around
Grab your phone, a tape measure, a 2-foot level, and a screwdriver. Start at the house and work outward.
- Foundation line. Is the gap where concrete meets the house open? Set the level on the slab. Is it tipped toward the house? (Caulking where concrete meets the house)
- Downspouts and sump outlet. Where does the water actually land? Look for washed-out soil and sunken splash blocks.
- Joints and cracks. Missing or torn caulk, weeds, and any edge where one side sits higher than the other. Measure the drop. (Concrete crack types)
- Slab corners. Step on them. Rocking, or a hollow sound when you tap with the screwdriver handle, points to a void under the slab.
- Surface. Flaking, popouts, plow scrapes, chipped edges.
- Pads and steps. Put the level on the AC pad and the stoop. (Sinking AC pad)
- Near trees. A humped slab next to a big tree is usually roots, not winter. (Tree roots lifting concrete)
Take photos from the same spots every spring. Year-over-year pictures are the easiest way to tell whether something is moving.
Rinse the Salt Off First
Salt doesn't quit when the snow does. Brine soaked into the surface and packed into joints keeps working on the concrete through every freeze-thaw night left in the season.
On the first days above freezing, hose off the apron, garage approach, walks, and garage floor, and flush out the joints. Plain water and a stiff brush are enough. Go easy on any spot that's already flaking; scrub it by hand rather than pressure washing it. Our hand-cleaning guide covers how, and concrete spalling causes explains what the salt is doing.
Sunk or Heaved? Wait for the Frost to Leave
A slab riding high on frozen soil in March may settle back by May. A slab that looks fine in March may drop once the soil under it thaws and drains. So look early, but judge late.
Once the ground has thawed and dried out, compare what you see against your March photos:
| What you see after the thaw | Likely cause | What to do |
|---|---|---|
| Slab sits lower than its neighbors, water pools on it | Settling, washout, or a void | A lifting candidate. See how concrete lifting works. |
| Slab rose in winter and came back down | Frost heave | Fix the drainage and seal the joints so less water gets under it. |
| Slab is higher and stays high near a tree | Roots | Foam can't lower a slab. See the tree roots article. |
| Slab rocks when you step on a corner | A void under one side | Foam fills voids as it lifts. |
Joints, Cracks, and the House Gap
Plows catch caulk that sits proud, freeze-thaw stretches it, and old sealant shrinks and pulls loose. Every open joint lets meltwater straight under the slab.
- Dig out failed sealant and clean the joint down to bare concrete.
- Wait for the right day: clean, dry, frost-free concrete at 40°F or warmer.
- Lift first if a slab sank. Caulking a sunken slab seals it in the wrong position. Lift, patch the drill holes, then seal the joints.
Our sealant comparison covers materials, and filling expansion joints walks through the job.
Downspouts and Sump Discharge
Spring is when both work hardest. Check for:
- Extensions knocked loose by the snowblower or plow.
- Splash blocks that sank or tipped back toward the house.
- Sump discharge dumping onto the driveway or walk, or right next to a slab. Point it toward the yard, well away from the concrete.
- Washouts along slab edges. Fill them with soil, tamp it, and slope it away from the slab.
Planning to bury an extension? Call Diggers Hotline at 811 before you dig. Here's how to extend downspouts the right way.
Spalling and Plow Damage
Walk the driveway edges and the apron. Look for chipped slab edges, scraped joints, and flaking. If the plow keeps catching the same raised edge, the slab next to it has usually sunk, and lifting that slab back up removes the lip.
Cleaning won't fix flaking, but sealing a solid slab can slow it down. For cracks the plow is making worse, see driveway crack repair.
Clean, Caulk, Then Seal
On a combined job, the order goes: clean, let it dry, lift and patch if needed, caulk, and seal once the caulk has cured. Cleaning comes first so caulk and sealer bond to clean concrete. Our cleaning guide covers that step.
Temperature decides when you can seal. Most of the penetrating sealer labels we checked list 40°F as the minimum air and surface temperature, and one also says not to apply if it's expected to drop below 40°F within 12 hours. Your product's label is the final word. Green Bay's normal low is about 35°F in April and 46°F in May, so realistic spring sealing starts around mid-May.
Pick the right type. For outdoor concrete here, penetrating silane or siloxane sealers are the go-to: they soak in, let the concrete breathe, leave no slippery film, and resist water and salt. Film-forming acrylics suit decorative concrete but wear faster and can get slick. See why seal concrete and choosing a concrete sealer.
New concrete waits. The data sheets we checked wanted concrete cured first, typically 14 to 28 days, with 28 days common.
Book Lifting Early
Spring is when sinking shows up, and it's also the start of lifting season, which runs from spring thaw to freeze-up. We don't lift on frozen ground.
Send photos as soon as you spot a problem. We'll quote from them, and the lift happens once the ground is ready. Fix the downspout in the meantime. Here's what lifting day looks like.
Most of this checklist, though, you can handle yourself: rinsing salt, sweeping, downspouts, a few tubes of caulk on level slabs, cleaning a patio. You don't need us for any of that. Call when a slab has sunk, the joint footage is more than you want to tackle, or the whole driveway needs a clean and seal.